1. Field of the Invention
The present invention relates to a packet forwarding system used in a network system, and more particularly to a packet forwarding system capable of controlling, among the forwarded packets, a control packet (or control traffic) for the purpose of network control and efficiency; the present invention also relates to a control packet controlling apparatus and a control packet processing method thereof.
2. Description of the Related Art
Generally, a router and a switch are representative examples of the devices that connect networks. The main function of the router or the switch is to transmit the data packet to a destination. In order to ensure that the data packets are transmitted to the right destination, a control packet management device has to be provided in order to have a control packet, which controls the network, be transmitted to a host for processing.
FIG. 1 is a schematic block diagram of a conventional control packet management device 110. As shown, the control packet management device 110 is provided with a host 120 which processes a control packet received from the control packet management device 110.
The control packet management device 110 has a queue 111 to temporarily store a control packet as inputted, and a control unit 113 to transmit the control packet stored in the queue 111 to a host 120 by the interrupt method.
As the control packet is inputted, the control packets are temporarily stored in the queue 111, and the control unit 113 transmits such temporarily-stored control packets to the host 120 by the interrupt method, i.e., the control unit 113 transmits such temporarily-stored control packets to the host 120 as soon as the control packet is received. More specifically, the control unit 113 checks the queue 111 to determine whether there is any control packet to be transmitted, and if so, sends out an interrupt signal to a CPU 121 of the host 120, notifying that there is a control packet to be transmitted for processing. At this time, the CPU 121 temporarily stops the current operation, activates the interrupt service routine, and records the control packet existing in the queue 111 with a register 123 to record the existing control packet in the register 123. The CPU 121 reads the control packets recorded in the register 123 and thus processes the read control packets.
As described above, the conventional control packet management device 110 uses a so-called ‘one-by-one interrupt’, by which an input control packet is read and directly transmitted to the host 120 one by one. Such ‘one-by-one interrupt’ requires a somewhat long period of time for the process of transmitting the input control packet to the host 120. Accordingly, when there is temporarily a great amount of traffic of control packets to be transmitted to the host 120, performance of the host 120 degrades and in the worse case, the host 120 can be shutdown.